Use of air purifiers has been exploded recently, mainly due to increasing air pollution levels experienced around big cities. Stand-alone air purifiers as well as air conditions affixed with the air purification function are commercially available. Generally, an air purifier operates in a manner of drawing in contaminated indoor air, and purifying the drawn air into clean air by filtering out dusts or odor particles entrained in the air. The air purifier thus includes a blower device to discharge purified air once the ambient drawn air is purified, and a filter to filter out dusts or odor particles entrained in the drawn air.
The filter has to be replaced periodically or non-periodically, as it is contaminated in the course of performing air purification function. The shortcoming of the related air purifier is that it is necessary for a user to manually demount the filter from interior of the air purifier to outside and observe it with his or her own eyes to check the contamination level of the filter mounted in the air purifier. As described, the related air purifier has drawbacks of requiring cumbersome filter checking process, not to mention unhygienic work environment issues which arise as the user touches the filter to demount the same outside the air purifier, during which contaminants such as dusts are left on the user's hands. Additionally, dusts may re-scatter from the filter to environment around the user, while the filter is separated from the air purifier and placed outside.